Python script to read 1-4 key presses and log it to the file, q to quit

keys.py

import termios, tty, sys, time

fd = sys.stdin.fileno()
old = termios.tcgetattr(fd)
tty.setcbreak(sys.stdin)

try:
    print('Waiting for key pressed [1,2,3,4] or [q] to quit')

    while True:

        key = sys.stdin.read(1)

        if key == '1' or key == '2' or key == '3' or key == '4':
            now = time.strftime("%Y-%m-%d %H:%M:%S")
            print('  ['+key + '] - key was pressed '+now)
            f = open('keys.csv', 'a')
            f.write(now+','+key + '\n')
            f.closed

        if key.lower() == 'q':
            sys.exit(0)

finally:
    termios.tcsetattr(fd, termios.TCSADRAIN, old)
    print('Bye.')